<template>
  <view>
    <!-- 自定义的搜索组件 -->
    <my-search @click="gotoSearch"></my-search>
    
    <view class="scroll-view-container">
      <!-- 左侧的滑动区域 -->
      <scroll-view class="left-scroll-view" scroll-y="true" :style="{ height: wh + 'px' }" >
        <view :class="['left-scroll-view-item', i === active? 'active' : '']" v-for="(item1, i) in cateList" :key="item1.cat_name" @click="active = i">{{ item1.cat_name }}</view>
      </scroll-view>
      <!-- 右侧滑动区域 -->
      <scroll-view scroll-y="true" :style="{ height: wh + 'px' }" >
        <view class="cate-lv2" v-for="item2 in subCateList" :key="item2.cat_name">
          <!-- 二级分类标题 -->
          <view class="cate-lv2-title">/ {{ item2.cat_name }} /</view>
          <!-- 三级分类列表 -->
          <view class="cate-lv3">
            <view class="cate-lv3-item" v-for="item3 in item2.children" :key="item3.cat_name" @click="gotoGoodsList(item3)">
              <image :src="item3.cat_icon" mode=""></image>
              <text>{{ item3.cat_name }}</text>
            </view>
          </view>
        </view>
      </scroll-view>
      
    </view>
  </view>
</template>

<script>
  export default {
    data() {
      return {
        // 当前设备可用的高度
        wh: 0,
        // 分类列表数据
        cateList: [],
        active: 0,
        subCateList: []
      };
    },
    watch: {
      // 侦听active的变化渲染右侧的
      active: function(val) {
        this.subCateList = this.cateList[val].children
      }
    },
    onLoad() {
      const sysInfo = uni.getSystemInfoSync()
      // console.log(sysInfo)
      this.wh = sysInfo.windowHeight - 50
      
      this.getCateList()
    },
    methods: {
      // 获取分类列表的数据
      async getCateList() {
        const { data: res } = await uni.$http.get('/api/public/v1/categories')
        if(res.meta.status !== 200) return uni.$showMsg()
        this.cateList = res.message
        this.subCateList = this.cateList[0].children
      },
      // 跳转到商品页面
      gotoGoodsList(item) {
        uni.navigateTo({
          url: '/subpkg/goods_list/goods_list?cid=' + item.cat_id
        })
      },
      gotoSearch() {
        uni.navigateTo({
          url: '/subpkg/search/search'
        })
      }
    }
  }
</script>

<style lang="scss">
.scroll-view-container {
  display: flex;
  .left-scroll-view {
    width: 120px;
    .left-scroll-view-item {
      background-color: #F7F7F7;
      font-size: 12px;
      text-align: center;
      line-height: 60px;
      &.active {
        position: relative;
        background-color: #fff;
        &::before {
          content: ' ';
          display: block;
          width: 3px;
          height: 30px;
          background-color: red;
          position: absolute;
          top: 25%;
        }
      }
    }
  }
}

.cate-lv2-title {
  font-size: 12px;
  font-weight: bold;
  text-align: center;
  padding: 15px 0;
}

.cate-lv3 {
  display: flex;
  flex-wrap: wrap;
  .cate-lv3-item {
    width: 33.33%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    margin-bottom: 10px;
    image {
      width: 60px;
      height: 60px;
    }
    text {
      font-size: 10px;
    }
  }
}
</style>
